Submission #1049015

#	Time	Username	Problem	Language	Result	Execution time	Memory
1049015		FanOfWilliamLin	Selling RNA Strands (JOI16_selling_rna)	C++14	100 / 100	211 ms	255932 KiB

selling_rna

#include <bits/stdc++.h>

using namespace std;

int get_val(char f) {
    if (f == 'A') return 0;
    if (f == 'G') return 1;
    if (f == 'C') return 2;
    return 3;
}

char get_char(int x) {
    if (x == 0) return 'A';
    if (x == 1) return 'G';
    if (x == 2) return 'C';
    return 'U';
}

const int NUMBEROFNODES = 2e6 + 5;
const int INF = 1e9;
struct Trie{
    struct Node{
        int child[4];
        int l, r;
        int exist;
    } nodes[NUMBEROFNODES];

    int cur;
    Trie() : cur(0) {
        memset(nodes[0].child, -1, sizeof(nodes[cur].child));
        nodes[0].l = INF; nodes[0].r = -INF;
        nodes[0].exist = 0;
    };

    int new_node() {
        cur++;
        memset(nodes[cur].child, -1, sizeof(nodes[cur].child));
        nodes[cur].l = INF; nodes[cur].r = -INF;
        nodes[cur].exist = 0;
        return cur;
    }

    void add_string(string s, int id) {
        int pos = 0;
        for (auto f : s) {
            int c = get_val(f);
            if (nodes[pos].child[c] == -1) nodes[pos].child[c] = new_node();
            pos = nodes[pos].child[c];

            nodes[pos].l = min(nodes[pos].l, id);
            nodes[pos].r = max(nodes[pos].r, id);
        }
        nodes[pos].exist++;
    }

    pair<int, int> get_range(string s) {
        int pos = 0;
        for (auto f : s) {
            int c = get_val(f);
            if (nodes[pos].child[c] == -1) return {-1, -1};
            pos = nodes[pos].child[c];
        }
        return {nodes[pos].l, nodes[pos].r};
    }

    void dfs(int pos, string& current_string, vector<string>& res) {
        for (int i = 1; i <= nodes[pos].exist; i++) res.push_back(current_string);

        for (int i = 0; i < 4; i++) if (nodes[pos].child[i] != -1) {
            current_string += get_char(i);
            dfs(nodes[pos].child[i], current_string, res);
            current_string.pop_back();
        }
    }

    vector<string> sort_strings() {
        vector<string> res;
        string current_string = "";
        dfs(0, current_string, res);
        return res;
    }
};

struct ReversedTrie{
    struct Node{
        int child[4];
        vector<int> ids;
    } nodes[NUMBEROFNODES];

    int cur;
    ReversedTrie() : cur(0) {
        memset(nodes[0].child, -1, sizeof(nodes[cur].child));
        nodes[0].ids.clear();
    };

    int new_node() {
        cur++;
        memset(nodes[cur].child, -1, sizeof(nodes[cur].child));
        nodes[cur].ids.clear();
        return cur;
    }

    void add_string(string s, int id) {
        reverse(s.begin(), s.end());
        int pos = 0;
        for (auto f : s) {
            int c = get_val(f);
            if (nodes[pos].child[c] == -1) nodes[pos].child[c] = new_node();
            pos = nodes[pos].child[c];
            nodes[pos].ids.push_back(id);
        }
    }

    int query(string s, pair<int, int> range) {
        reverse(s.begin(), s.end());
        int pos = 0;
        for (auto f : s) {
            int c = get_val(f);
            if (nodes[pos].child[c] == -1) return 0;
            pos = nodes[pos].child[c];
        }

        int l = lower_bound(nodes[pos].ids.begin(), nodes[pos].ids.end(), range.first) - nodes[pos].ids.begin();
        int r = upper_bound(nodes[pos].ids.begin(), nodes[pos].ids.end(), range.second) - nodes[pos].ids.begin() - 1;

        return r - l + 1;
    }
};

vector<string> sort_strings(vector<string> v) {
    Trie list;
    for (auto s : v) list.add_string(s, -1);
    return list.sort_strings();
}

signed main() {

    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

    int n, m;
    cin >> n >> m;

    vector<string> v;
    for (int i = 1; i <= n; i++) {
        string s;
        cin >> s;
        v.push_back(s);
    }
    v = sort_strings(v);

    Trie trie1;
    ReversedTrie trie2;
    for (int i = 1; i <= n; i++) {
        trie1.add_string(v[i - 1], i);
        trie2.add_string(v[i - 1], i);
    }

    while (m--) {
        string p, q;
        cin >> p >> q;

        pair<int, int> range = trie1.get_range(p);
        if (range.first == -1) cout << "0\n";
        else cout << trie2.query(q, range) << "\n";
    }

}

• Subtask 1: 10 / 10
• Subtask 2: 25 / 25
• Subtask 3: 25 / 25
• Subtask 4: 40 / 40